861363993 has 48 divisors (see below), whose sum is σ = 1427608320. Its totient is φ = 459242784.

The previous prime is 861363989. The next prime is 861364001. The reversal of 861363993 is 399363168.

It is a happy number.

It is not a de Polignac number, because 861363993 - 2² = 861363989 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (861363913) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 184830 + ... + 189432.

It is an arithmetic number, because the mean of its divisors is an integer number (29741840).

Almost surely, 2^861363993 is an apocalyptic number.

It is an amenable number.

861363993 is a deficient number, since it is larger than the sum of its proper divisors (566244327).

861363993 is a wasteful number, since it uses less digits than its factorization.

861363993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4706 (or 4699 counting only the distinct ones).

The product of its digits is 629856, while the sum is 48.

The square root of 861363993 is about 29349.0032709801. The cubic root of 861363993 is about 951.4710332746.

The spelling of 861363993 in words is "eight hundred sixty-one million, three hundred sixty-three thousand, nine hundred ninety-three".